Traditionally, devices for the removal and installation of springs from the brake assemblies of motor vehicles include a pair of pivoted scissor-like arms. The end of one arm is formed at a right angle to the arm, having a pointed end thereon. The end of the other arm includes an arcuate hook that is directed inwardly toward the one arm of the device. The end of the handle of the device is adapted to release the spring at the top of an old style brake drum by engaging a connector and turning it. In use, the arms of the device are opened to place the hook of the other arm between the end of the spring and the shoe of the drum, the pointed end of the one arm being in contact with the brake lining located on the opposite side of the brake shoe.
Examples of such traditional brake spring pliers are disclosed in U.S. Pat. Nos. 1,938,102 issued to Hill; 1,953,930 issued to Dyal; and 2,264,391 issued to MacLeod. A similar device that also applies pressure with an arm having a pointed hook formed thereon is disclosed in U.S. Pat. No. 2,474,940 issued to Hansen.
While being useful for their purpose, use of such devices can easily result in the pointed end thereof damaging the brake lining, especially when applying pressure therewith. Such a problem is emphasized by the fact that such linings are relatively susceptible to being damaged and are quite expensive to replace.
In an attempt to solve this problem, several devices, arrangements and methods of which I am aware, wherein the device does not touch the brake lining during use, have been disclosed in the following United States Letters Patent:
______________________________________ U.S. Pat. No. Inventor(s) Year of Issue ______________________________________ 1,917,878 O'Donnell 1933 1,949,343 Wood 1934 2,042,287 Allievi, et al. 1936 2,274,981 Grubb 1942 2,489,434 Riccio 1949 2,507,622 Brugmann 1950 2,666,256 White 1954 2,839,820 Bates 1958 3,355,791 Castoe 1967 3,602,973 Mata 1971 3,891,185 Lett 1975 4,064,978 Wunderlich 1977 4,870,737 Navarro 1989 ______________________________________
Unfortunately, each of the above-mentioned references has one or more drawbacks in that they either: exert pressure on the brake shoes, etc., of the brake assembly, which elements are ill-adapted to withstand such pressure; or, they fail to provide the beneficial leverage that is provided by having a fulcrum, an element that is especially important when removing high tension springs, such as those found in, for example, large trucks.
Additionally, none of the device, arrangements and/or methods noted above are adjustable, so that the hooks thereof that are provided may be oriented for use on either shoe of the drum. Thus, they may only be used on one of the shoes. This limits the applicability and use of these devices.
Recently, a new type of brake drum has also been employed. The brake springs of these new type of brake drums are positioned and attached differently than those of the old type of brake drums. These differences between the old and the new types of brake drums means that the devices noted above, which are designed for use only with the old type of brake drum, are not readily adaptable to be utilized on the new type of brake drums.
Finally, it is noted that the devices disclosed in the above-noted references are not readily adjustable for use with both the old and the new types of brake drums, as well as for use with brake drums of different sizes.
Accordingly, it can be seen that there remains a need for a brake spring pliers that provides a fulcrum for providing the desired leverage for installation/removal of a brake spring, which pliers minimize the potential of damaging the brake lining, and which pliers are readily adjustable, so as to be adaptable for use on both old and new types of brake drums of varying sizes and designs.